Yobs are putting lives at risk by pelting buses with missiles as they travel through a Sheffield suburb, say police.
Since December 29 four buses have been damaged by vandals hurling stones and bricks at vehicles travelling along Staniforth Road, Darnall.
Police officers investigating the incidents are now travelling on buses undercover in a bid to catch the culprits in the act.
They also want members of the community to report those responsible.
Inspector Chris Lewis, who oversees policing in Darnall, said the vandals are putting lives at risk.
“Since December 29 we have had four buses reported as being damaged as they were travelling along Staniforth Road,” said Insp Lewis.
“All four suffered smashed windows and two of them were also disabled by people using the emergency stop button at the rear of the buses.
“On each occasion a group of Asian youths were reported to us. They were wearing hoods and masks each time.
“They need to realise that their actions are placing members of the public in danger - not only the bus drivers and passengers but other road users and pedestrians.
“If a bus swerves after being hit with a missile there is a risk of it colliding with other vehicles or pedestrians, which is why we are taking this seriously.
“We are working with bus operators and are carrying out covert operations using the buses in a bid to identify the culprits.
“We also hope that this acts as a deterrent and makes those responsible think twice about their actions.”
The four incidents reported to the police have all happened at various locations along Staniforth Road between 5.30pm and 8.40pm.
A number of bus companies have been affected.
Witnesses to the vandalism attacks or anyone with information about those responsible should call South Yorkshire Police on 101 or Crimestoppers on 0800 55511.